Portable cbane



UNITED STATES PATENT OFFICE.

C. SNYDER AND S. M. SMITH, OF HAWLEY, PENNSYLVANIA.

PORTABLE CRANE.

Specification of Letters Patent No. 30,358, dated October 9, 1860.

To all whom t may concern:

Be it known that we, CHARLES SNYDER and SARAH MrLLs SMITH, both or' Hawley, in the county of layne and State of Pennsylvania, have invented a new and Improved Portable Crane; and we do hereby declare that the following is a full, clear, and exact description of the saine, reference being had to the accompanying drawings, making a part of this specification, in which- Figure l is a side elevation of the iinproved crane. Fig. 2 is a front view of the same.

Similar letters of reference indicate corresponding parts in both figures.

This invention is a portable extension crane, which is so constructed that it can be readily set up from place to place in any building, from eight to iifteen feet, more or less, between the floors.

The invention consists in combining with an extension mast and adjustable crane arm an extension brace for supporting the arm at any elevation to which it is capable of being placed; all as will be hereinafter described and represented.

To enable those skilled in the art to fully understand our invention we will proceed to describe its construction and operation.

In the drawings, A is the lower portion of the mast, and B is the upper portion, which latter is capable of sliding up and down in the portion A. The mast is mounted in the usual manner by a pivoted foot bearing a, and a point C is a pinion spur wheel, the teeth of which engage with rack teeth on the sliding part of the mast, by means or' this wheel C, it having its bearings in the stationary part of the mast, the movable part B, of the mast may be raised or lowered thus increasing or diminishing the height ot' the mast. The block c, is a stop-block for pinion wheel C, and d, is the crank by which the pinion is operated.

E is the movable crane arm which is attached to, and projects out at right angles from a movable sliding head-block F, through which block the upper (smaller) portion of the mast passes. This crane arm can be elevated or depressed on its portion of the mast by means of a pinion C', which has its bearings in the head block F, andv engages with the teeth of the rack on the movable portion of the mast.

c is the crank arm for pinion C', and c', is the stop block for fixing the crane arm in an elevated position.

The crane thus consists of three principal parts, viz: the lower and stationary portion of the mast, the upper and movable portion which works in the lower portion, and the crane arm with its block, which moves up and down on the movable portion B, of the mast.

G is a brace for supporting the arm E, either in an elevated or depressed state, which brace consists of two racks g, g, which are jointed respectively to the portion A, of the mast, and to the crane arm E; these racks are brought together with their teeth. on the outside, which teeth are pitched in opposite directions. Now these toothed bracing rods are held together by metal straps or stirrups 72., h, which allow the braces to be extended in a direction with their length, but'which prevent the braces from slipping back after they are extended; they thus form an extension brace for the crane arm E, which supports it in any position. The crane is then rigged in the usual manner. The chain g, passes over a drum G, and is wound up by gearing G2, G3, and crank H. The chain passes from the drum G, up and over two pulleys on the arm E, and under a pulley in block J, it is iinally attached by a hook or other suitable means to the end ot the crane arm E, as represented in Figs. l and 2, of the drawings.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is

The combination with the extension mast and adjustable crane arm E, of the eXtension braces, when the same are constructed, and operate substantially as and for the purposes herein set forth.

CHAS. SNYDER. SARAH M. SMITH. Vitnesses:

I. B. SNYDER, J. F. SMITH. 

